From e5f7e211b6aa19d5398abe3d91a508bf7f06ed54 Mon Sep 17 00:00:00 2001 From: Davide Caratti Date: Sun, 27 Sep 2020 16:08:21 +0200 Subject: [PATCH] ip6gre: avoid tx_error when sending MLD/DAD on external tunnels similarly to what has been done with commit 9d149045b3c0 ("geneve: change from tx_error to tx_dropped on missing metadata"), avoid reporting errors to userspace in case the kernel doesn't find any tunnel information for a skb that is going to be transmitted: an increase of tx_dropped is enough. tested with the following script: # for t in ip6gre ip6gretap ip6erspan; do > ip link add dev gre6-test0 type $t external > ip address add dev gre6-test0 2001:db8::1/64 > ip link set dev gre6-test0 up > sleep 30 > ip -s -j link show dev gre6-test0 | jq \ > '.[0].stats64.tx | {"errors": .errors, "dropped": .dropped}' > ip link del dev gre6-test0 > done Reported-by: Jianlin Shi Signed-off-by: Davide Caratti Signed-off-by: David S. Miller --- net/ipv6/ip6_gre.c | 33 ++++++++++++++++++++++----------- 1 file changed, 22 insertions(+), 11 deletions(-) diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 3a57fb9..931b186 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -707,6 +707,17 @@ static int prepare_ip6gre_xmit_ipv6(struct sk_buff *skb, return 0; } +static struct ip_tunnel_info *skb_tunnel_info_txcheck(struct sk_buff *skb) +{ + struct ip_tunnel_info *tun_info; + + tun_info = skb_tunnel_info(skb); + if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX))) + return ERR_PTR(-EINVAL); + + return tun_info; +} + static netdev_tx_t __gre6_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, struct flowi6 *fl6, int encap_limit, @@ -734,10 +745,9 @@ static netdev_tx_t __gre6_xmit(struct sk_buff *skb, const struct ip_tunnel_key *key; __be16 flags; - tun_info = skb_tunnel_info(skb); - if (unlikely(!tun_info || - !(tun_info->mode & IP_TUNNEL_INFO_TX) || - ip_tunnel_info_af(tun_info) != AF_INET6)) + tun_info = skb_tunnel_info_txcheck(skb); + if (IS_ERR(tun_info) || + unlikely(ip_tunnel_info_af(tun_info) != AF_INET6)) return -EINVAL; key = &tun_info->key; @@ -908,7 +918,8 @@ static netdev_tx_t ip6gre_tunnel_xmit(struct sk_buff *skb, return NETDEV_TX_OK; tx_err: - stats->tx_errors++; + if (!t->parms.collect_md || !IS_ERR(skb_tunnel_info_txcheck(skb))) + stats->tx_errors++; stats->tx_dropped++; kfree_skb(skb); return NETDEV_TX_OK; @@ -917,6 +928,7 @@ tx_err: static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) { + struct ip_tunnel_info *tun_info = NULL; struct ip6_tnl *t = netdev_priv(dev); struct dst_entry *dst = skb_dst(skb); struct net_device_stats *stats; @@ -964,15 +976,13 @@ static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb, * for native mode, call prepare_ip6gre_xmit_{ipv4,ipv6}. */ if (t->parms.collect_md) { - struct ip_tunnel_info *tun_info; const struct ip_tunnel_key *key; struct erspan_metadata *md; __be32 tun_id; - tun_info = skb_tunnel_info(skb); - if (unlikely(!tun_info || - !(tun_info->mode & IP_TUNNEL_INFO_TX) || - ip_tunnel_info_af(tun_info) != AF_INET6)) + tun_info = skb_tunnel_info_txcheck(skb); + if (IS_ERR(tun_info) || + unlikely(ip_tunnel_info_af(tun_info) != AF_INET6)) goto tx_err; key = &tun_info->key; @@ -1065,7 +1075,8 @@ static netdev_tx_t ip6erspan_tunnel_xmit(struct sk_buff *skb, tx_err: stats = &t->dev->stats; - stats->tx_errors++; + if (!IS_ERR(tun_info)) + stats->tx_errors++; stats->tx_dropped++; kfree_skb(skb); return NETDEV_TX_OK; -- 2.7.4